| 摘要 |
According to the invention, a magnetoresistive sensor for scanning a magnetic multipole wheel is proposed, which scans many uniformly disposed magnetic pole pairs. The sensor has four magnetoresistive resistors, which are connected electrically as a Wheatstone bridge with two half-bridges and which output a sine-wave and cosine-wave signal, respectively. To suppress the third and/or fifth harmonic of the scanning signal, it is proposed that the spacing between the two half-bridges be selected such that it is not equal to half the wavelength (lambda). For the third harmonic, the spacing d=lambda/3 is preferably selected, so that the half-bridges are offset by a phase angle of 120°. To suppress the fifth semiharmonic, three identical sensors with a suitable spacing are connected together. The measured signals are averaged, so that the result is a field course with the third and fifth harmonics filtered out.
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